Thailand is run by a military dictatorship which oversees a democratically elected parliament. There were some shenanigans in the last election, and the PM was kicked out after being convicted of some crimes. His brother-in-law is acting PM now. Protesters who want the PM's party ousted have taken over Government House, so the government moved to the old airport. This would be like the Gavin Newsom running to Mill Valley if his office was overrun by H8 supporters.
There was some bloodshed when the occupation took place and later as well, but since then it's been shouting matches. The protesters announced today they would make a "final" move by occupying the government offices at the old airport. The government decided they did not want any more fighting, so they did not arm the police and allowed the protesters to take over the offices unopposed. The officials had already left the building, a couple of them taking off their suits and ties and nonchalantly waltzing to the car park, one of them smiled and waved at protesters who did not recognize him disguised as a civilian.
The police have also been mostly successful keeping the pro-government counter-protesters away from the anti-government ones. This is important - the 1976 coup saw armed pro-government vigilantes killing dozens of anti-government protesters, which gave the army an excuse to stage a bloody coup.